Removable case and method for opening and closing a pressurized can provided with a frangible obturator

ABSTRACT

A method and device for opening a drink can provided with a frangible obturator which can be pushed back inside the can using a tongue that is fixed in a horizontal position in the middle of the lid by means of a rivet on which the tongue can pivot as a lever to produce an opening which is later closed by a movable case that is adapted on the tongue which is pivoted around the river in order to move onto the opening.

BACKGROUND OF THE INVENTION

The invention relates to a method for opening the frangible obturator ofa container of the drink can type according to the preamble of the firstclaim, using an handling device or handler subsequently reusable forclosing said drink can. The method is of particular interest in that itprovides numerous advantages in the manufacturing and filling of drinkcans, as well as in their handling, storage and distribution.

In the prior art, some devices for closing such containers are alreadyknown, comprising a cylindrical body, a bottom and a lid on which anaperture may be provided with a globally sectoral size smaller than thelid size, using a frangible obturator that is pushed inside thecontainer through the leverage provided by the tear-off tab maintainedin the middle and above said lid by a rivet.

Among these prior art devices, the one described in the European PatentEP-0 558 422 is without doubt the most remarkable one in that itcomprises a case removably assembled on or around the tear-off tab,before or after opening a metallic cylindrical can including a lid witha frangible obturator so as to form a movable tab pivoting around therivet enabling the tear-off tab to be handled on the upper part of thelid, wherein this case will on the one hand fit onto said tear-off tab,and on the other hand, due to adequately shaped external peripheraledges, clip around the peripheral lid crimping rim on the cylindricalcan body, this rim then serving as an external rail for facilitating thecase's circular displacements above the lid.

An important advantage of this device is that the removable case may bepositioned on the can after the filling and the crimping of the lid,which was an important advance as compared with prior solutions.

In order to provide the consumer with a drink can equipped with itsclosing case, right from the start, a fitting operation was thereforerequired before the product's sales distribution; this fitting operationconsisted of three main phases:

lifting the pull-tab without tearing the frangible obturator,

propelling the removable case for fitting it on and around said tab,

clipping by vertically pressing the case onto the crimping rim.

This fitting operation, technologically feasible and economicallyaffordable, does however meet with a first series of drawbacks: itrequires carrousel or comb type fitting robots that must operate at avery high rate with a good deal of precision for lifting the metal tabin a first phase, without thereby piercing the frangible obturator; onthe other hand, the fitting robots must be installed in the fillingpremises of the drink manufacturer, furthermore, placing the case on thelid of the can creates excessive thickness on the peripheral rim thatmay hinder transport and storage of such cans traditionally stacked oneupon the other.

SUMMARY OF THE INVENTION

To overcome these drawbacks, in accordance with the invention, a methodis provided for opening and closing a drink can type containerconsisting of a usually metallic cylindrical body on which is crimped,through a peripheral crimping rim, a lid devoid of any tear-off tab orpull-tab but provided with a frangible obturator that may be torn apartalong a line of least resistance implemented for that purpose in orderto provide a partial aperture by using a handling instrument, alsocalled a case, that is fitted in, removably, through a capture shaftwhich works together with a linking joint fixed by a rivet to the centerof said lid so as to allow the case to both pivot in the vertical planeby lifting its end close to the peripheral crimping rim around saidjoint, to act as a lever and push in the frangible obturator, by meansof the other end provided with a reinforced leading edge for thatpurpose, and further move in the horizontal plane around the same jointso as to close the aperture by being clipped on the peripheral crimpingrim.

For better comparison with the aforementioned closest prior art devices,i.e. European Patent EP-0 558 422, the preferred term case willsystematically be used for designating the handling instrument orhandler according to the invention and this, for all the text thatfollows.

According to a first alternative of the method just described, the casethat is used for opening and closing drink cans, is positioned on thelid in a very simple manner; the case is indeed fitted onto the linkingjoint by mere vertical pressure, wherein said joint is itself shaped tobe accommodated in a capture shaft located in the bulk of the case sothat the leading edge at the front of said case will be normal to thefrangible obturator and the rear portion of this case will be normal tothe crimping rim, so as to form firstly the tab element for pushing inthe frangible obturator, and if required, secondly the closing elementby horizontally pivoting the case around the rivet over a 180° anglesector.

It will be well understood that such an alternative provides undeniableadvantages over the prior art in that the automatic fitting of the caseis thereby considerably facilitated as it is no longer required to liftup the tab; mere vertical pressure is enough to bring the case onto thecan and to clip it on the linking joint and the crimping rim,simultaneously.

However, as such a method results in positioning a case on the crimpingrim right from the start, according to another particularlysophisticated alternative of the invention, it is envisaged to join thecase to the lid in two steps: first, by vertically pressing the caseonto the linking joint that will fit into a capture shaft provided inthe bulk of the case, then by a radial translation in a planesubstantially horizontal in parallel to the lid bringing the leadingedge of the case normal to the frangible obturator and the rear portionof the case close to the peripheral rim, so as to form firstly, hereagain, the tab element for pushing in the frangible obturator, and ifrequired, secondly the closing element by horizontally pivoting the caseby 180° around the rivet.

According to the latter alternative, new advantages appear that are hererelated to the fact that the case, which may be translated radially onthe lid, may lie entirely in the interior space defined by the crimpingrim and the lid face.

It is then understood that the thereby positioned case is no longer anobstacle for the lid crimping tool with the lucky consequence that itmay be assembled on the lid before crimping.

Moreover, such a method simplifies the fitting of the case andeliminates some fitting robots on the filling lines which furthermoreavoids disturbing the process; the method also allows to makesubstantial savings of metal due to the partial elimination of the priorart tear-off tabs and save part of the folding operations related tothis same tab. Finally, such a method, that avoids excessive plasticthicknesses on the peripheral rim, with the case being temporarilymaintained in the middle of the lid, is particularly advantageous fortransport and storage of the drink cans that will be done as usual.

BRIEF DESCRIPTION OF THE DRAWINGS

Hereafter, two main alternatives of the device implementing the methodaccording to the invention will be described, provided by way ofnon-limiting examples of the invention to better highlight furtheradvantages and features with reference to the drawings wherein:

FIG. 1 illustrates a first embodiment of the removable case;

FIG. 2 corresponds to section II—II of FIG. 1;

FIGS. 1a and 2 a illustrate a second embodiment of the removable case inplan and section views;

FIGS. 3a 1-c 2 illustrate three different alternatives of the linkingjoint between the case of FIGS. 1 and 2, and the lid of the can;

FIGS. 4a-c are vertical sectional views schematically illustrating theassembly of a case in accordance with the first simplified alternativeof the method, on a schematically and partially represented can, andshowing in cut-out views at a larger scale the detail of two embodimentsfor snapping the linking joint into the bulk of the case;

FIGS. 5 to 10 are vertical sectional views schematically illustratingthe assembly of a removable case in accordance with the mostsophisticated alternative of the method on the linking joint riveted inthe middle of the lid of a schematically and partially illustrated can;FIG. 9 schematically shows the case in the position where it is clippedonto the peripheral rim after opening the frangible obturator,illustrated in FIG. 8; FIG. 10 illustrates the case of FIG. 9 afterrotation by 180° so that it will overlap the aperture detailed in FIGS.8 and 9.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to the figures, two preferred alternatives of the removablecase 1 implementing the method as set forth above, for opening andsubsequent closing of containers 2 of the drink can type will bedescribed hereafter.

Such containers generally include a cylindrical body usually obtained bydrawing a soft steel or aluminum flat blank, a necking 3 being madelater on near the upper edge of said body onto which an equally metalliclid 4 is attached by perimetric crimping creating a particularlyadvantageous peripheral rim 5 as will be stated later; the lid 4 isprovided with a frangible obturator 6, in a known manner, which when ithas been torn along a line of least resistance made for this purpose,provides an aperture 7 of a globally sectoral shape, allowing the drinkcontained in the can 2 to be consumed. The cutting out of the obturator6 is generally performed in the prior art by means of a tear-off tabnormally comprising an eyelet grip, manufactured from thin sheet metalthrough adequate folding. This tear-off tab is firmly secured to the can2 by means of a rivet 8 in the middle and above the lid 4 so that whensaid tab is lifted it expels the obturator 6 towards the inside of thecontainer through leverage on the rivet 8, before returning naturally toa position slightly inclined with regard to its initial position.

Referring to FIG. 3 of the drawings, and in accordance with one of theessential features of the invention, the tear-off tab used in priorsolutions is omitted and replaced by a removable case 1 as illustratedin the embodiments of FIGS. 1 and 2.

Instead of the tear-off tab, a linking joint 9 is provided that ismaintained in the middle of the lid 4 by a rivet 8. This linking joint 9essentially includes a horizontal axis 90 maintained in a horizontalposition a little above the upper face of lid 4 by a bendable link piecefirmly securing axis 90 to lid 4.

Axis 90 is such that it is able to cooperate with case 1 provided with acapture shaft for that purpose, inside which axis 90 will clip or fit tofirmly secure case 1 to lid 4, as will be described later.

In accordance with particular embodiments illustrated in FIG. 3, axis 90may be assembled on a bendable linking part 91, e.g. from the same metalas the lid, as illustrated in FIG. 3a 1, i.e. on the side opposite tothe frangible obturator 6 with regard to the rivet 8 or vice-versa onthe same side as illustrated in FIG. 3b 1, or else may be made directlyfrom the rivet 8 using a vertical prominence 92 as illustrated in FIG.3c 1; the linking joint 9 comprises a bendable element, advantageouslyof a metal similar to that of lid 4, with a general L shape, therectangular vertical branch 91 of which horizontally supports axis 90 atits longitudinal edge, the length of which is shorter than that of axis90 so as to create on both sides of branch 91 projecting axis portions93 and 94; the horizontal branch of the element is for firmly securingthe linking joint 9 to lid 4 by means of a rivet 8 from which it is made(FIGS. 3c 1-2) or that crosses it (FIGS. 3a 1-2 and 3 b 1-2) allowingthe centered joint to rotate on rivet 8.

Naturally, one or the other of these embodiments or their equivalentswill be preferred depending on the manufacturing criteria in the generaleconomy of the inventive device.

According to a first alternative implementing the method according tothe invention, and referring to FIGS. 1 and 2, and to FIGS. 4a-c, case 1in the general shape of an angular sector (without this shape beingactually mandatory) is obtained preferably by injecting some plasticmaterial or metal inside a mould provided for mass production with highthroughput. Each case 1 includes an upper side 11 and a lower side 12for resting on lid 4, both sides being brought together by substantiallyvertical side walls 13 and 14 capable of forming together a volume forreceiving additional joints able to cooperate closely with axis 90 andits link to lid 4, so as to form a device allowing the frangibleobturator 6 to be opened and subsequently closed.

For that purpose, and in accordance with this first low cost alternativeof case 1, a capture shaft 10 is provided from the lower side 12 of thecase 1, so as to extend vertically into the bulk of the case,symmetrically on both sides of its longitudinal plane of symmetry,forming a longitudinal container with an axis perpendicular to thelongitudinal axis of symmetry of case 1 substantially coinciding with aradius of lid 4; such a shaft 10 is able to receive freely but withminimum play, the axis 90 that may thus fit gradually into it as case 1approaches the lid surface 4 through a vertical translation movement asillustrated by the arrow A in FIG. 4b.

In accordance with the drawings, especially with FIGS. 4a-b, the captureshaft 10 according to a first embodiment has an entrance area 101 whosevertical section in the longitudinal plane of symmetry is advantageouslytriangular, flared towards the bottom and narrowing vertically up to anecking 15 topped by a cavity 10 of circular section, capable ofreceiving axis 90 of linking joint 9 when the case is in contact withthe lid; obviously, the aperture area of necking 15 is smaller than thediameter of axis 90 so as to retain it inside cavity 102, after a forcedpassage into the necking at the time of clipping.

According to another embodiment detailed by the view of FIG. 4c, shaft10 has an entrance area 101 with vertical walls that are parallel oradvantageously inclined from bottom to top; at the line where axis 90 isattached onto its linking part 91, 92 each wall is provided with atleast one flexible tab 103, 104 extending substantially horizontallytowards the other wall where it may, if required, rest vertically afterhaving been stressed from bottom to top by axis 90 upon penetrating intocavity 102, during assembly; the tabs 103 and 104 are dimensioned so asto reach the line where axis 90 is attached to its base, and/or underthe protruding portions 93, 94 of axis 90 and resting on the facingwall, forming so many vertically retaining elements of axis 90 insidethe bulk of case 1.

In accordance with this first alternative, case 1 furthermore includesat one of its ends an appendix 16 forming a reinforced leading edge soas to act, as will be explained below, on the frangible obturator 6 thattears apart along a line of least resistance, in order to provide adefinitive aperture 7. At the other end of case 1, means for linking thecase to the crimping rim 5 are provided; such means are for instancedescribed in the already mentioned European Patent EP 0 558 422. It willalso be noted that these linking means 17 notably allow the crimping rim5 of lid 4 on can 2 to be used as a rail for circularly guiding case 1when it is used for closing the aperture 7 obtained by rotating saidcase 1 around rivet 8, bringing its lower side 12 normal to aperture 7for closing it; advantageously, lower side 12 of case 1 has a bulge 18,the shape of which is substantially the same as the general shape ofaperture 7 and the thickness is sufficient for fitting in snugly thereinand improving the closure; obviously and as set forth in the EuropeanPatent, the linking means 17 cooperating with the crimping rim 5 willcomplete the compression of the bulge area 18 inside aperture 7.

It should be noted that the entrance of the capture shaft 10 ispositioned on the lower side 12 of the case at a distance from the endcomprising the linking means 17 so that when it is on the rim 5, joint 9fits exactly into shaft 10.

Thus formed, this first alternative embodiment for case 1 first of allprovides the function of opening the drink can, e.g. delivered with case1 mounted thereon, after the filling and crimping the lid 4 on can 2;the user then has to clear the linking means 17 from rim 5 so as todrive case 1 into vertical rotation around the linking joint 9 firmlysecured to the middle of lid 4 by means of rivet 8. In this verticalrotational motion, the reinforced edge 16 rests on the frangibleobturator 6 that it pushes in through leverage joint on 9. Once theobturator 6 has been pushed inside can 2, all that has to be done is totilt back case 1 in a reverse rotation for clipping, along arrow B ofFIG. 4b, the case 1 on rim 5 by means of its linking joints 17, withcase 1 then being in a position to be used for another closure when theliquid contained inside can 2 has been consumed; for that purpose, allyou have to do is perform a rotation by 180° along rim 5 that serves asa circular guide for bringing the bulge area 18 normal to aperture 7 andforming a relatively efficient closure as explained previously.

Referring to FIGS. 1a and 2 a and to FIGS. 5 and 10, particularlyefficient and preferred alternative of a removable case 1 will now bedescribed implementing the general method according to the invention.

In its general structure, the case 1 corresponding to this secondalternative is globally the same as the case 1 of the previousalternative, except regarding the linking part which cooperates withlinking joint 9 and more specifically with axis 90 firmly secured to lid4 by means of a center rivet 8.

According to FIGS. 1a and 2 a showing the ventral portion of case 1 andits section at the linking device, case 1 has a capture shaft 20positioned perpendicularly to its longitudinal axis, but placedsubstantially in the middle of case 1 between its two ends 16 and 17respectively serving as a leading edge 16 for removing the frangible cap6 and the clipping means 17 on the crimping rim 5, as mentioned for theprevious alternative.

According to this preferred embodiment, the shaft 20, allowing axis 90to be fitted vertically therein when case 1 is brought closer to lid 4,is associated with a translation channel 21 opening onto shaft 20 andextending into a horizontal or inclined plane in the direction of thereinforced edge 16 over such a distance that axis 90, penetrating shaft20 and following the translation channel 21 through a recess of the casein the direction of the crimping rim in a plane substantially parallelto the plane of the lid and along one of its radials, is in frontabutment with the translation channel, when the rear linking means 17are in position for clipping onto the crimping rim 5. Besides, it willbe observed that the front end of the translation channel 21 in thisalternative, coincides exactly with the position of the capture shaft 10of the first alternative, which is clearly shown in FIGS. 1 and 1a.

Naturally, the translation channel 21 ensuring radial motion of case 1after it has been assembled on joint 9 must be such that when it isengaged, axis 90 can no longer escape from said channel and firmlysecures case 1 to lid 4, vertically. For that purpose, on each flank 24vertically delimiting channel 21, a groove 22 is provided laterallywidening the bottom 23 of channel 21 over a height equivalent orslightly greater than the diameter of axis 90, providing channel 21 witha T-shaped transversal vertical section.

The depth of grooves 22 is selected to fit the projecting parts 93 and94 FIGS. (3 a 1-c 2) of axis 90 snugly with regard to linking part 91 ofaxis 90. Advantageously, the distance separating both vertical blanks 24of the translation channel 21 matches the width of said linking part 91.

Finally, it is clear that the grooves 22 open onto the bottom of captureshaft 20, which enables axis 90, after its vertical displacement whencase 1 is fitted onto lid 4, to enter into the lateral grooves 22 forallowing a radial translation of the case in the direction of thecrimping rim 5 on which it will be clipped subsequently, as will beexplained in the following lines with reference to FIGS. 5 to 10.

Obviously, like for the first alternative, the capture shaft 20 may beimproved, e.g. by providing a flared tapered entrance up to alongitudinal necking similar to necking 15 of shaft 10, above which thetranslation channel 21 opens as described before.

The advantage of this embodiment is that it is possible to clip case 1in the middle of lid 4 before the filling and the crimping on the can 2,in a single vertical fitting operation.

Can 2, as partially and schematically illustrated in FIG. 5, is preparedwith a lid 4 provided with a frangible obturator 6 (represented with asolid line in all figures), is crimped on can 2 after its filling, whichprovides a peripheral rim 5 at an extra height in comparison with theside of lid 4. The case 1 shaped according to the second alternativeembodiment is shown vertically along arrow C on lid 4 so that thecapture shaft 20 is brought to be normal to axis 90 positionedhorizontally near the center of lid 4 according to any of thealternatives detailed in FIG. 3.

According to this first vertical approach, the lower side 12 and morespecifically the bulge 18 of case 1 is resting on lid 4 so that it isentirely comprised within the surface defined by the peripheral rim 5according to FIG. 6; at this moment, the linking joint 9 is entirelyplaced into the capture shaft 20 ensuring the required retention of thecase on the can 2 which may thus be stacked, stored and dispatched inany already known manner. Besides, it should be noted that case 1 may beassembled on the linking joint 9 prior to crimping lid 4, i.e. beforefilling, without thereby hindering the subsequent crimping operation.

In accordance with FIG. 7, when the liquid contained in can 2 is to beconsumed, it is advisable to then remove cap 6 using of course case 1 inaccordance with the inventive method. According to FIGS. 7 and 8, inorder to open can 2, the operator must grab the end of case 1 closest torim 5, lift it up slightly to avoid the extra height of said rim 5 andimpart translational motion in the direction of arrow D, FIG. 7. Thistranslation D will have the effect that axis 90 is radially displacedalong translation channel 21, linking element 91, 92 of axis 90 slidingbetween two lateral flanks 24 of said translation channel, and theprotruding parts 93, 94 of axis 90 following two lateral grooves 22opening, as seen, onto the bottom of the capture shaft 20 and extendingto the front of translation channel 21 where axis 90 abuts and thusfirmly secures case 1 to lid 4; the only possible movement is thenrotational motion in the direction of arrow E in FIG. 8; when thisrotation is extended vertically, the reinforced leading edge 16 of case1 then contacts the frangible area of the obturator 6 and through theleverage around the bendable linking joint 9 maintained by rivet 8, theobturator 6 is pushed back inside the can in accordance with arrow F inFIG. 8. Of course, the obturator 6 thus pushed back stays in thisposition and provides the aperture 7 for consuming the liquid. Forbetter clearing of aperture 7, case 1, in accordance with FIG. 9, isthen pushed back by reverse rotation along arrow G in FIG. 9 and clippedonto rim 5 by means of the linking joints 17 as described above. It willbe noted that this clipping onto the rim 5 is required as otherwise case1 would stay in an inclined position due to the deformation of thelinking part 91, 92 stressed in the movement of FIG. 8 when theobturator is opened. Finally, and then using rim 5 as a guide rail, theuser who wishes to temporarily close can 2 for later consumption, willbe able to bring, through mere horizontal rotation around rivet 8according to arrow R of FIG. 10, case 1 normal to aperture 7 into whichwill fit bulge 18 thus providing a virtually sealed closure which infact only depends on compression of the case onto aperture 7.

According to a final feature of the invention, it is possible toincrease the closing compression; for this purpose, the bottom 23 of thetranslation channel 21 may be inclined with regard to the flat bottom ofbulge 18. The slope of the translation channel results from a slopeimparted to bottom 23 from capture shaft 20 to lid center, i.e. towardsaxis 90. Thus, as case 1 is translated towards peripheral rim 5, asindicated by arrow D in FIG. 7, it is gradually tightened between itssupporting side and the upper face of lid 4 so that upon closing (FIG.10), the pressure of case 1 on aperture 7 is increased significantly, atleast when it is clipped onto the rim 5.

It is clearly apparent that all different combinations of thealternative embodiments as described above using for instance thedifferent shapes of linking joints connected to the lid or the case, orother equivalent solutions not described, would not depart from thescope of the invention in as far as the new alternative embodiment wouldimplement the inventive method; in particular, this would be the case ifaxis 90 were to be replaced by a sphere attached to rivet 8 cooperatingwith a capture shaft and, if required, a translation channel, e.g. oftubular shape.

What is claimed is:
 1. A case for opening and closing a drink can thathas a cylindrical body having a rim whereon is crimped a lid with afrangible obturator, the obturator being adapted to open along a line ofleast resistance to form an aperture, and a link member having a firstpart that is generally parallel to and spaced from the lid and a secondpart that attaches the first part to the lid, the case comprising: acapture shaft adapted to receive the link member and to hold the linkmember while the case is rotated in a first plane transverse to the lidand in a second plane parallel to the lid; a rear edge with a clipadapted to removably clip to the crimped rim of the can when saidcapture shaft receives and holds the link member; a reinforced leadingedge adapted to engage the frangible obturator and create the aperturewhen the case is rotated in the first plane; and a bottom adapted toclose the aperture, wherein rotating the case in the second plane, afterrotation in the first plane, reorients the bottom over the aperture, andclipping said clip to the crimped rim closes the aperture, wherein saidcapture shaft has a longitudinal axis perpendicular to the second plane,a chamber at an end of the longitudinal axis for receiving the linkmember, wherein an entrance to said chamber has means for holding thelink member, wherein said capture shaft has walls that get closertogether approaching said chamber and said means for holding the linkmember comprises a throat with a diameter smaller than a diameter ofsaid chamber.
 2. The case of claim 1, wherein said capture shaft haswalls parallel to the longitudinal axis and said means for holding thelink member comprises flexible tabs that extend across said captureshaft.
 3. A case for opening and closing a drink can that has acylindrical body having a rim whereon is crimped a lid with a frangibleobturator, the obturator being adapted to open along a line of leastresistance to form an aperture, and a link member having a first partthat is generally parallel to and spaced from the lid and a second partthat attaches the first part to the lid, the case comprising: a captureshaft adapted to receive the link member and to hold the link memberwhile the case is rotated in a first plane transverse to the lid and ina second plane parallel to the lid; a rear edge with a clip adapted toremovably clip to the crimped rim of the can when said capture shaftreceives and holds the link member; a reinforced leading edge adapted toengage the frangible obturator and create the aperture when the case isrotated in the first plane; and a bottom adapted to close the aperture,wherein rotating the case in the second plane, after rotation in thefirst plane, reorients the bottom over the aperture, and clipping saidclip to the crimped rim closes the aperture, wherein said capture shafthas a longitudinal portion perpendicular to the second plane and alateral portion parallel to the second plane.
 4. The case of claim 3,wherein said longitudinal portion of said capture shaft has walls thatget closer together approaching said lateral portion.
 5. A case foropening and closing a drink can that has a cylindrical body having a rimwhereon is crimped a lid with a frangible obturator, the obturator beingadapted to open along a line of least resistance to form an aperture,and a link member having a first part that is generally parallel to andspaced from the lid and a second part that attaches the first part tothe lid, the case comprising: a capture shaft adapted to receive thelink member and to hold the link member while the case is rotated in afirst plane transverse to the lid and in a second plane parallel to thelid; a rear edge with a clip adapted to removably clip to the crimpedrim of the can when said capture shaft receives and holds the linkmember; a reinforced leading edge adapted to engage the frangibleobturator and create the aperture when the case is rotated in the firstplane; and a bottom adapted to close the aperture, wherein rotating thecase in the second plane, after rotation in the first plane, reorientsthe bottom over the aperture, and clipping said clip to the crimped rimcloses the aperture, wherein said bottom has a bulge that engages theaperture when said clip is clipped to the crimped rim and closes theaperture.
 6. A method for opening and closing a drink can having acylindrical body on which is crimped, through a peripheral crimping rim,a lid provided with a frangible obturator that may be torn apart along aline of least resistance in order to provide a partial aperture by usinga case that is removably fitted, through a capture shaft, on a linkingjoint fixed to a center of the lid, the method comprising the steps of:pivoting the case in the vertical plane by lifting one end close to theperipheral crimping rim around the linking joint, so that the case actsas a lever and pushes in the frangible obturator by means of another endprovided with a reinforced leading edge; and rotating the case in thehorizontal plane around the linking joint so as to close the aperture byclipping the one end on the peripheral crimping rim, wherein the case issecured to the lid by vertically pressing the linking joint into acapture shaft of the case, where a leading edge of the case is normal tothe frangible obturator and a rear portion of the case is normal to theperipheral crimping rim so as to form the one end for pushing in thefrangible obturator.
 7. A method for opening and closing a drink canhaving a cylindrical body on which is crimped, through a peripheralcrimping rim, a lid provided with a frangible obturator that may be tornapart along a line of least resistance in order to provide a partialaperture by using a case that is removably fitted, through a captureshaft, on a linking joint fixed to a center of the lid, the methodcomprising the steps of: pivoting the case in the vertical plane bylifting one end close to the peripheral crimping rim around the linkingjoint, so that the case acts as a lever and pushes in the frangibleobturator by means of another end provided with a reinforced leadingedge; and rotating the case in the horizontal plane around the linkingjoint so as to close the aperture by clipping the one end on theperipheral crimping rim, wherein the case is secured to the lid byvertically pressing the linking joint into the capture shaft of thecase, then moving the case through a radial translation in a horizontalplane in parallel to the lid, wherein a leading edge of the case isnormal to the obturator and a rear portion of the case is close to theperipheral crimping rim so as to form the one end for pushing in thefrangible obturator.
 8. The method according to claim 7, furthercomprises the step of radially translating the case in the horizontalplane from a pre-opening position so that the case stays completelyenclosed inside a space defined by the peripheral crimping rim to apost-opening position, wherein the one end clips onto the peripheralcrimping rim so as to be superimposed over the aperture and thus closethe aperture.